| 主权项 |
1. A developing device comprising:
a developer carrying member for carrying a developer comprising a toner and a carrier; a magnet, provided inside said developer carrying member, including a plurality of magnetic poles with respect to a rotational direction of said developer carrying member; a developing chamber for feeding the developer to said developer carrying member; a non-magnetic blade member for regulating an amount of the developer to be coated on said developer carrying member; and a guiding portion for guiding the developer from above to said developer carrying member with respect to a direction of gravitation, wherein said guiding portion is provided, opposed to said blade member and said developer carrying member, upstream of said blade member with respect to the rotational direction of said developer carrying member, wherein a distance from a developer feeding start position of said guiding portion where feeding of the developer toward said developer carrying member starts to said blade member is 2 mm or more with respect to the rotational direction of said developer carrying member, and when a magnetic force at a surface of said developer carrying member with respect to a direction normal to said developer carrying member is Fr, the magnetic poles are provided so that a ratio of an integrated value FrNear obtained by integrating the magnetic force Fr from said blade member to a position of 2 mm upstream of said blade member with respect to the rotational direction of said developer carrying member to an integrated value FrAll obtained by integrating the magnetic force Fr from said blade member to the developer feeding start position with respect to the rotational direction of said developer carrying member is 60% or more. |
